1. Field of the Invention
This invention relates generally to various heterocyclic compounds, preferably nitrogen containing heterocyclic compounds, useful as additives for lubricant and fuel compositions. The additives of the present invention when formulated with a lubricant or fuel composition provide improved fuel economy and friction modification in an internal combustion engine. The heterocyclic compound additives of the present invention may be reacted with a hydrocarbyl carboxylic acylating reactant or a hydrocarbyl phenolic reactant to form a higher molecular weight product to impart greater solubility and dispersancy in various lubricant and fuel compositions as well as providing improved fuel economy.
2. State of the Art
Reducing fuel consumption and improving the operation of internal combustion engines has been an objective in the industry since the early 1970's. Since that time, a number of additives have been developed in an attempt to achieve this objective.
For example, U.S. Pat. No. 4,326,972 discloses a lubricating oil formulated with a specific sulfurized composition and a basic alkali metal sulfonate to provide improved fuel economy of internal combustion engines.
U.S. Pat. No. 4,289,635 discloses various molybdenum compounds of phosphorus acids which are useful for formulating with lubricating compositions for improved fuel economy of internal combustion engines.
Heterocyclic amino, specifically amino piperidine compounds, have been disclosed in the patent literature. U.S. Pat. No. 3,971,792 discloses a process for the manufacture of 4-amino-3-aminomethyl piperidine which are disclosed as being useful as curing agents for epoxide resins.
Great Britain Pat. No. 1,122,110 discloses 4-imino-3-cyano piperidines wherein the process for preparing these compounds is disclosed.
None of the foregoing disclosures teach the heterocyclic compounds of the present invention useful for providing friction modification and improved fuel economy in lubricant and fuel compositions.